Test handlers are used in the semiconductor industry for testing electronic devices, such as integrated circuits, semiconductor chips and the like. There is a constant demand for such electronic devices to be produced at less cost and in smaller dimensions, increasing the challenges faced when designing apparatus to test such electronic devices.
Test contactors comprised in test handlers generally position the electronic device for testing by a tester. Contact pins of the test contactor are connected to the electronic device during testing to make electrical contact with the device under test (“DUT”). The test contactor is usually incorporated as part of or subsequently coupled to a tester depending on the type of device being tested.
In the case of light-emitting electronic or photonics devices, such as light-emitting diodes (“LEDs”), the tester typically includes sensors for measuring the intensity and/or quality of the light emitted. A challenge faced when testing LEDs is to be able to effectively observe the light emitted by the LED with sensors which are located at a certain distance from the LED. An unblocked line of sight should preferably be maintained between the LED and the sensors while the device is held securely and electrically connected at the testing position.
One traditional type of test contactor for LEDs comprises an insulation socket with a contact pin incorporated in the socket. An LED is inserted into the insulation socket to make electrical contact with the contact pin so as to illuminate the LED. An optical test is then conducted. Thus, the position of the test contactor is fixed at the testing position. Automation of the testing process may comprise the steps of using a pick arm to transfer the LED to the insulation socket, inserting the LED into the insulation socket with the pick arm to make contact with the contact pin in order to light up the LED for testing, and then removing the LED from the insulation socket. A disadvantage of this approach is that the pick arm typically has to be positioned over the insulation socket, and therefore blocks some of the light emitted from the LED. The resulting test is hence less accurate since some of the light is blocked. The movement of the pick arm to pick and position one LED at a time at the insulation socket is also relatively slow.